Fish of Coastal New Jersey

Found from saltwater parts of estuaries and bays of 330 m (Ref. 26938). Inhabit inshore areas. Prefer waters of 10°-21°C. Feed mainly on decapod crustaceans, bivalves, polychaetes, squids and fishes (Ref. 3824). Breed while inshore (Ref. 6902). Oviparous. Distinct pairing with embrace. Young may tend to follow large objects, such as their mother (Ref. 205). Eggs are oblong capsules with stiff pointed horns at the corners deposited in sandy or muddy flats (Ref. 205). Egg capsules are 5.1-8.9 cm long and 3.8-5.7 cm wide (Ref. 41249, 41307, 41301, 41358). less ↑

Rhinoptera bonasus is one of fifteen species of elasmobranch fishes recorded in the Indian River Lagoon (Snelson and Williams 1982). The dorsal side is brown to olive lacking spots or other markings. The ventral side of the cownose ray is white or yellowish-white with brown edges. The pectoral fins, sometimes referred to as wings, are long and pointed. The square shaped projecting snout has an indentation in the center giving the impression that it is bi-lobed. Two small fins (rostra) project from the head. The mouth is small and located on the ventral side of the ray. The tail is whip-like with a spine at the base just posterior to a small dorsal fin. A defensive venomous barb is located at the base of the spine. Species of cownose ray are sometimes only distinguishable by the morphology and number of teeth. less ↑

Found on continental and insular shelves and upper slopes, ranging from shallow inshore waters and the intertidal to 200 m, occasionally down to 579 m (Ref. 244). Occasionally found in freshwater. It is doubtful that this species can live in fresh water for an extended period of time (Ref. 244). Feeds on large crustaceans, mainly crabs, but also heavily on lobsters (Homarus) (Ref. 244). Probably non-territorial. Off the Atlantic coast of the USA, this species is migratory (Ref. 244). Viviparous (with a yolk-sac placenta), with 4 to 20 young in a litter. Longevity given as 7 years (Ref. 775) but appears too low. Utilized fresh, dried-salted, and smoked (Ref. 9987). less ↑

The sandbar shark spends the majority of its time near the sea bottom, where it patrols continuously for prey (4), such as small bottom-dwelling fishes, molluscs and crustaceans (2). Whilst the diet of the adult consists primarily of fish, the pups appear to feed more on soft blue crabs (7). Despite its size and large triangular teeth, the sandbar shark has never been blamed for attacks on humans, preferring instead to stick to its live fish meals (2). Like most other members of the Carcharhinidae family, the sandbar shark is viviparous, giving birth to between 1 and 14 pups in each litter (2). The size of the litter varies depending on the size of the mother, with large females giving birth to larger litters (2). Pregnancy is estimated to last from 8 to 12 months (2), and appears to differ between geographical locations (8) (9). The time of year in which the pups are born also varies slightly, but all females move inshore to shallow nursery areas to give birth (2) (8) (9). These nursery grounds are separated from the normal ranges of adults (9), and presumably offer the young a calm, food-rich environment in which to begin their lives. The females leave these coastal areas soon after giving birth, while the young remain in the nursery grounds until winter (9), when they move into warmer and deeper water (2). A common feature of sharks is their slow growth rate and low reproductive output. Estimates of the age at which the sandbar shark matures range from eight to ten years in Hawaii (10), to between 12 and 15 years of age in the Northwest Atlantic Ocean (11). Females give birth every other year at most (2). Populations of sandbar sharks appear to segregate by age (6). less ↑

Blue sharks are viviparous, giving birth to live young after a gestation period of nine to twelve months (6) (7). Up to 135 pups can be born per litter, partially depending on the size of the female, but the average is 25 to 50 (5) (6). Maturity is reached at approximately five to six years old and blue sharks are known to have lived to 20 years (7). Although often observed cruising slowly and sluggishly the blue shark is capable of rapid movement if it is excited or feeding (6). This species will often circle its prey before moving in to attack it. Blue sharks primarily feed upon relatively small prey, such as bony fish and squid, but will also take larger prey including mammalian carrion (1). less ↑

The Ocean Sunfish or Mola (Mola mola) is the world's heaviest bony fish. The distinctive body shape is laterally compressed and appears bluntly terminated to the rear, as if the tail had been lopped off. Molas have a reduced skeleton, with fewer vertebrae than any other fish. Metamorphosis from larva to adult is remarkable in that, unlike most fish, Molas pass through two distinct larval phases—a typical Tetraodon pufferfish-like larval and another highly transformative stage resulting in the complete absorption of the tail (Fraser-Brunner 1951). Molas have been claimed to be the most fecund vertebrates known, with a single female reportedly producing several hundred million eggs at once (Schmidt 1921, cited in Pope et al. 2010).

Molas have a very broad global distribution, occurring in both temperate and tropical waters of the Atlantic, Indian, and Pacific Oceans. Due to their primarily pelagic (open water) distribution, studying their ecology and behavior is challenging. They are most easily observed basking at the surface, a behavior for which several functions have been proposed, including warming themselves after deep dives into cold water and presenting themselves to seabirds and other fishes that remove parasites (such as Pennella copepods) from their bodies (Abe et al. 2012; Pope et al. 2010 and references therein). Although Molas were long believed to be sluggish swimmers, drifting passively in ocean currents, based on investigations in recent years (e.g., Cartamil and Lowe 2004; Sims et al. 2009; Dewar et al. 2010) it is now clear that Molas do not necessarily travel with prevailing currents and instead appear to be relatively active predators that are capable of migrating at least moderate distances, perhaps in response to shifts in regional productivity and temperature. Gelatinous zooplankton (such as jellyfishes, salps, and pyrosomes) comprise a large fraction of the diet of these fish, although Syväranta et al. (2012) have used stable isotype analyses to argue that the extent of dependence of Molas on gelatinous zooplankton may be overstated, as was suggested by Pope et al. (2010) (but see Logan and Dodge 2013 and Harrod et al. 2013). Stable isotope studies of Molas in the Mediterranean Sea by Cardona et al. (2012) supported the assertion that gelatinous zooplankton are at least a major component of the diet. Hays et al. (2009) compared foraging depths for Molas and Leatherback Turtles (Dermochelys coriacea)--the heaviest bony fish and the heaviest sea turtle, both of which are believed to feed heavily on gelatinous zooplankton. They found that while Molas can feed from the surface to depths greater than 500 m, Leatherbacks are limited to relatively shallow waters (<200 m), presumably because of the constraint that they must return to the surface to breathe air.

Although Molas are caught and sold in only a few parts of the world, such as Japan and Taiwan, in recent years they have been taken incidentally in substantial numbers in many fisheries, including the swordfish drift gillnet fishery off California and Oregon (U.S.A.), the illegal Spanish driftnet swordfish fishery off the Gibraltar Straits in the Mediterranean, and the the tuna and swordfish longline fishery off the coast of South Africa (Dewar et al. 2010 and references therein).

The taxonomic treatment of fishes in the family Molidae has fluctuated considerably through time. Current molecular, morphological, and distributional data appear to support the recognition of at least two species in the genus Mola: M. mola and the far less familiar M. ramsayi (which is likely limited to the southern hemisphere), as well as possibly at least one more. Because of the unresolved taxonomic issues in the genus Mola, it is possible that some studies supposedly done on M. mola may actually apply to a different closely related species. Two additional species are included in the family Molidae, Masturus lanceolatus and Ranzania laevis. The Molidae are closely related to the Tetraodontidae (pufferfishes) and Diodontidae (porcupine fishes). (Bass et al. 2005; Yoshita et al. 2009; Pope et al. 2010 and references therein)

Pope et al. (2010) provide a wide-ranging and thorough review of the limited available data on the taxonomy, morphology, ecology, and conservation of Molas. The oceansunfish.org website is a rich source of information about molas.

(Bass et al. 2005 and references therein; Pope et al. 2010 and references therein) less ↑

Adults found in deep seaward reefs; occasionally entering coastal bays. They feed primarily on fishes such as the bigeye scad, also on invertebrates (Ref. 4233). Small juveniles associate with floating plants or debris in oceanic and offshore waters. Juveniles form small schools or solitary (Ref. 5213). Eggs are pelagic (Ref. 4233). Utilized fresh and frozen; eaten pan-fried, broiled and baked (Ref. 9987). Reported to cause ciguatera in some areas (Ref. 26938). less ↑

The albacore tuna forms schools, which can be up to an astonishing 30 kilometres wide (3). These enormous schools are sometimes associated with floating objects, such as sargassum weeds, and they may also form mixed schools with other tuna species, such as skipjack, yellowfin and bluefin tuna (2). In these schools, the albacore tuna undertakes great migrations in search of the best feeding and spawning grounds, strongly influenced by large oceanic phenomena such as El Niño (5) (6). Albacore tuna are able to reach impressive speeds, of up to 80 kilometres per hour, due to their highly evolved circulatory system that reduces the loss of heat generated by increased muscular activity. This allows them to maintain their body temperature at a higher level than the surrounding water, keeping their muscles warm and working efficiently (3). Unlike many fish, albacore tuna are not able to pump water over their gills to obtain oxygen from the surrounding water, and therefore need to swim constantly with their mouth open, to force water over their gills. A high volume and pressure of blood, and great haemoglobin concentration, all increases the ability of the fish to absorb the essential oxygen (3). Albacore tuna are believed to be pelagic spawners, meaning that the female releases her eggs, and the male his sperm, into open water, often near the water's surface (3). A female albacore tuna is capable of producing two to three million eggs per spawning season, which are released in at least two batches (2); however, the majority of these eggs will not survive to be adults (3). The tiny eggs are just one millimetre in diameter and are enclosed in an oil droplet to enable them to remain buoyant in the ocean. The eggs are fertilized by the male, and the resulting fertilized eggs develop rapidly, with hatching occurring in less than 48 hours (3). The large albacore tuna is one of the top carnivores within the ocean regions it inhabits, and it preys voraciously upon smaller schooling fish such as sardines and anchovy, and squid, consuming around 25 percent of its weight every day. The albacore tuna itself becomes prey for larger species of tuna, billfish and sharks (3). less ↑

The golden tilefish, or great northern tilefish, Lopholatilus chamaeleonticeps, is a marine bottom dwelling fish of the tilefish family (Malacanthidae), found on the western Atlantic continental shelf from Nova Scotia to Surinam. It is not found in the Carribean, but does live in the gulf of Florida. Lopholatilus chamaeleonticeps means “crested tilus with a chameleon-like head.” A bottom dwelling fish, it lives in burrows that it makes in the sediment or among rocks and ledges along the continental shelf, at depths between 200-1400 feet, feeding on a variety of bottom-dwelling invertebrates and occasionally other fish. Tilefish burrows have been found to be very dense in some areas, transforming the sea bottom landscape to hilly tussocks. Tilefish are thought to have an important impact on the continental shelf ecology, hence were designated a keystone species by ichthyologist Ken Able in 1986. These large fish, which reach a weight of over 50 pounds and length of 44 inches, can live for longer than 45 years. Despite their large size, the golden tilefish were not discovered until 1879, when a schooner captain caught the first specimen off the coast of Massachusetts in 1879. Tilefish were soon found to be excellent eating and abundant and their discovery spurned a new fishing industry in the next several years. However, in 1882, soon after its discovery the tilefish experienced a devastating die-off, in which an estimated billion tilefish floated dead in waters north of Delaware Bay. Research on the species led to the conclusion that this near annihilation of the species was caused by a shift in the flow of the Gulf Stream up the continental shelf, temporarily diverting these warmer waters over far deeper waters. Tilefish, which were found to live in a very specific region defined by the constant warm temperatures (between 47-53 degrees F) are intolerant to colder temperatures but thought to be unable to follow the Gulf Stream which no longer flowed over a bottom habitat. The population, thought for years to be extinct, rebounded and slowly increased in numbers such that they were discovered again ten years later. Currently, Environmental Defense Fund (EDF) categorizes golden tilefish as highly susceptible to overfishing, and populations especially in the US Gulf of Mexico and South Atlantic are depleted. Turner (1986) and Barans and Stender (1993) also indicate that fishing has drastically reduced Golden tilefish stock and reduced northern populations. Tilefish are most commonly caught by longline, sometimes in bottom trawls, and are a popular sport fish. The EDF also warns that these southern populations are high in mercury, that women and children should not eat them; men should limit their consumption to once/month.

(American Littoral Society; Bigelow and Schroeder 1953; Environmental Defense Fund 2011; Jones and Schmidtke 2012; Steimle et al. 1999) less ↑

Found usually over sandy or muddy bottoms in coastal waters to about 60 m depth. Occurs in nursery and feeding grounds in river estuaries during summer and fall. Juveniles often stay in the estuarine waters throughout the year. Feeds mainly on worms, small crustaceans and organic detritus. A small specimen of this species was caught in Tokyo Bay, Japan, probably brought in with the ballast water of a ship (Ref. 10325). less ↑

The striped bass (Morone saxatilis) is a highly prized sportfish, which, although anadromous (meaning it migrates between salt and freshwater) can live its full life in fresh water. They are sleek silver fish that sport dark longitudinal stripes and are also known as Atlantic striped bass, stripers, linesiders, rock, pimpfish, or rockfish. Striped bass are one of six species belonging to the Moronidae family (temperate basses); they are not related to the black basses (which are in the sunfish family Centrarchidae). Striped bass commonly reach a length of 120 cm (3.9 feet), and are thought to live up to 30 years. Native to the Atlantic coastline and drainage waters of North America, the striped bass has been widely introduced to large reservoirs across the United States for recreational fishing, and also for the purpose of controlling populations of non-native gizzard shad (Dorosoma cepedianum). “Stripers” have also been introduced into the pacific coast of North America, and into waters in Ecuador, Iran, Latvia, Mexico, Russia, South Africa, and Turkey. Although their numbers declined in the early 1980s due to overfishing, subsequent management plans and a presidential order signed by George W. Bush in 2007 have returned them to healthy, "not overfished" (according to The Atlantic States Marine Fisheries Commission) status. Striped bass are the state fish of Maryland, Rhode Island, South Carolina, and the state saltwater fish of New York, Virginia, and New Hampshire.

(Wikipedia 2002; Executive order 13449; Shepherd, 2006) less ↑

Occurs on sandy bottom. Feeds on shrimps, crabs, other crustaceans, squid, bivalves and small fishes. Produces loud, drumming sound by vibrating its swim bladder (Ref. 9988). Used both for food and fish meal; other uses include bait for lobster traps and flatfish, handlines, pet food and fertilizer. Utilized fresh and frozen; also used for caviar ; can be broiled and baked (Ref. 9988). less ↑

Occur in streams, rivers, muddy or silt-bottomed lakes (Ref. 5951); usually in permanent streams with continuous flow. Hide during the day in undercut banks and in deep pools near logs and boulders. Feed on larvae of Ephemeroptera, Odonata, Plecoptera, Coleoptera, Trichoptera, and Lepidoptera, as well as gastropods, oligochaetes, amphipods, isopods, mysids, and fish from the families Percidae, Cyprinidae, Ictaluridae, Catostomidae and Anguillidae (Ref. 9593). Migrate in autumn to the Sargasso Sea to spawn (Ref. 3242). Sexual maturity occurs approximately in less than10 years and up to 40 years in freshwater (Ref. 57533). Larvae (transparent leptocephali shaped somewhat like a willow leaf) hatch and develop at sea to metamorphose into elvers in nearshore waters and estuaries (Ref. 57533). Adults are caught with eel pots and trot lines. Elvers and glass eels are caught with fine mesh fyke nets and dipnets. Catadromous species. (Ref. 26938). Maximum depth reported taken from Ref. 57178. less ↑

The winter flounder, Pseudopleuronectes americanus, (also known as black back or lemon sole) is a valuable commercially- and recreationally-fished flatfish. Native to western Atlantic waters, winter flounder are a common North American flatfish inhabiting sandy or muddy bottoms between Newfoundland, Canada and Georgia, USA. Adults prefer water temperatures of 12-15oC; they live inshore in the fall and winter, spawning in relatively shallow waters in the spring or early summer, then often (although not always, depending on food availability, water temperatures and possibly light intensity) migrate offshore, where they are found to depths 50 fathoms, for the warmer months. Unlike the eggs of other flounder species in the same area, winter flounder eggs sink to the bottom, usually in clusters. Winter flounder is a right-eyed ("dextral") flatfish that typically grows to 3-4 pounds, 58 cm (larger on Georges bank) and lives up to 15 years. Small-mouthed, winter flounders feed opportunistically on small invertebrates and larval fish, using primarily vision to locate food. Young and adult flounders are sensitive to waters high in sediment, which restrict feeding and this species is vulnerable to human activity because they spend much time in shallow water. Winter flounder are managed as three distinct natural groupings in the US: Gulf of Maine, southern New England-Mid-Atlantic, and Georges Bank, and three in Canadian waters: western Scotian Shelf eastern Scotian Shelf, and the southern Gulf of St. Lawrence. Heavily harvested, NOAA reports the US fishery has severely declined and although their most recent assessment has a high degree of uncertainty, all three US stocks are likely overfished.

(Bigelow and Schroeder 2002; Decelles and Cadrin 2011; Hendrickson, Nitschke and Terceiro 2006; NOAA Fishwatch; Pereira et al. 1999; Wikipedia 2011) less ↑

Adults usually prefer hard sandy substrate where they can burrow; can exploit a broad range of lower and mid-estuary habitats including salt marsh creeks and seagrass beds, which usually have muddy or silty substrates , as well as sand flats (Ref. 26621). Occur in bays, lagoons and shallow coastal waters. Utilized fresh and frozen; can be steamed, fried, boiled, microwaved and baked (Ref. 9988). Exported fresh to Japan for sashimi. less ↑

Found inshore in summer, but at least some moving into deeper water in winter. Adults are found in near surface waters (Ref. 38984), usually in shallow areas overlying continental shelf, in greatest abundance immediately adjacent to major estuaries (Ref. 4639). Juveniles are also generally pelagic, with smallest size groups farthest up river (Ref. 38986). Form large and very compact schools, both of juveniles and adults. Migrate north - south; also in and out of bays and inlets. Feed by filtering phytoplankton (diatoms (Ref. 5951)) and zooplankton (small crustaceans, annelid worms and detritus (Ref. 5951)). High water temperatures apparently limit breeding. Spawn probably all year; nursery areas in estuaries. Larvae are pelagic (Ref. 38985), probably spend about a month in waters over continental shelf (Ref. 38983), entering estuarine waters at about 10 mm and larger (Ref. 844). Marketed fresh, salted, canned or smoked. Mainly used for production of oil, fertilizer and fishmeal (Ref. 188). Parasites found are isopods, copepod, cestodes and trematodes (Ref. 37032). less ↑

More commonly found in shallow tidal areas with muddy bottoms and brackish waters, tolerating a wide range of salinities (virtually fresh to fully saline or hypersaline). Found only in spring and summer in the tidal portion of the Ochlockonee River, Florida. Feed mostly on Mysis and copepods, also small fishes, gastropods and isopods. Breed off North Carolina from late April to mid-July, perhaps through to August. Used to some extent to make anchovy paste (Ref. 189). less ↑

The mummichog, Fundulus heteroclitus, is a killifish in the family Fundulidae native to brackish and coastal waters along the Eastern North American seaboard from Florida to the Gulf of St. Lawrence. Known for its hardiness and tolerance of a wide range of salinity, oxygen levels, temperature and pollution in their environment, they also have a broad diet including diatoms, a range of invertebrates, fish and fish eggs and sea grass. Mummichogs have been used widely as an experimental fish since the end of the nineteenth century, in studies such as embryology, regeneration, developmental genetics, and starting in about 1930, in studies of endocrinology and toxicity. In addition, mummichogs have been included in biology experiments on space missions such as Spacelab 3 and Bion 3. In 1973 a pair of mummichogs were the first space fish on a voyage on Spacelab 3, investigating the role of otolith (earbone) organs. They are used to stock small ponds for mosquito control, and for bait.

(Atz 1986; Kraft, Carlson, and Carlson 2006; Webster’s online dictionary; Wikipedia 8 February 2012; Wikipedia 17 December 2011) less ↑

Adults are found on both shallow and deep sand flats among grass (Ref. 12342, 39154, 39155), inshore in saltwater creeks, rivers, bays, sounds (Ref. 39156), and deep channels within lagoons (Ref. 39155). Probably more dense over mud than shell or calcareous bottom (Ref. 39157). Also found in open ocean over continental shelf (Ref. 4639). A solitary (Ref. 26340) voracious predator that lurks in shallow bays and shore waters; burrows in bottom sediments. Juveniles are pelagic, and readily collected from open ocean, usually near land in vicinity of or in shallow water (Ref. 4639). Oviparous, newly hatched larvae are found near the surface at depths from 27 to 46 m (Ref. 39159). Salinity range 4.0-60.0 ppt (may include juveniles), more abundant above 10.0 ppt and 30.0 ppt (Ref. 39158, 39162, 39050). Commonly caught by anglers but considered a nuisance. less ↑

The oyster toadfish, Opsanus tau, also known as the ugly toad, oyster cracker and "bar dog", is a toadfish native to the western Atlantic in shallow waters between Massachusetts and Florida. A tadpole-shaped bottom dweller with a large mouth, its cryptic coloration make it well camouflaged in crevices on rocky/sandy/muddy substrates and reefs, jettys or wrecks from which the oyster toadfish ambushes its prey of a diverse range of fish and invertebrates. Like most toadfishes (family Batrachoididae), males of this species are known for attracting females to a nest by generating a deep grunting sound by vibrating their swimbladder. Oyster toadfish are hearty fish, able to withstand being out of water for up to 24 hours, and can live in polluted waters. They commonly grow to about 30 cms. While edible, they are not commonly eaten, perhaps because of their grotesque appearance. Opsanus tau has been used as a research animal in labs to investigate such topics as muscular contraction (the muscles wiring its swimbladder twitch faster than any other known vertebrate muscle), diabetes, drug metabolism and toxicology. They are also a valuable neurological model for vestibular system disorders, including balance disruption, dizziness, and motion sickness; this research involved sending two fish into space on shuttle mission STS-95 in 1998 to examine the effect of gravity on the vestibular system, a topic important to astronauts. The oyster toadfish’s species name, tau, derives from the shape of one of the fish’s vestibular canals which resembles the Greek letter tau.

(Marine Biological Laboratory Labnotes 1997; Wikipedia 2012; Woods Hole National Oceanographic Institute) less ↑

The American anglerfish Lophius americanus, also called goosefish, is a monkfish in the family Lophiidae; a ground dweller native to the eastern coast of North America. While eaten by humans, it is a fish of lesser importance than other food fish in the region, such as cod, and Greenpeace International recently added L. americanus to its seafood red list, indicating it has a very high risk of being sourced from unsustainable fisheries.

The American anglerfish’s unique appearance cannot be confused with other species in the regions where it is caught: it has a large mouth, more than twice the width of the tail, containing several spines and strong teeth that enable it to snare prey (fish, squid, cuttlefish, and sometimes carrion) larger than itself. Its body is flattened dorso-ventrally to allow it to hide on the sea floor. An ambush predator, the American anglerfish spends most of its time sitting still on sandy or rocky surfaces. The front of the head carries erectile spines, one of which functions as a lure for prey, with a tip resembling a small organism or piece of algae. The pectoral fins are like wide fans behind the head, which it uses to “walk” along the ocean floor.

Lophius americanus can live several decades, grow to 140 cm long (although 100 cm is a more usual size), and weigh up to 22.6 kg (the greatest recorded weight). (Wikipedia 2012)
less ↑

Found on soft muddy and sandy bottoms, but never on rocks, gravel or shells. Juveniles live along the coasts at shallow depths (4-6 m); adults migrate to deeper waters, generally to between 110 and 130 m, and in some instances, to over 550 m. Juveniles live in scallops (Placopecten magellanicus) and remain close to scallop beds until they mature (Ref. 9988). They prefer temperatures of 8-10°C (Ref. 5951). Feed on shrimps, amphipods and other crustaceans, also on squid and herring, flatfish, mackerel and others. Utilized fresh, dried or salted and frozen; also small fish are used for fishmeal ; eaten steamed, microwaved and baked (Ref. 9988). Maximum depth reported from Ref. 57178. less ↑

Found in small shoals on rough, rock, gravel, or pebble bottoms. Generally keeps far from the shore, near the bottom, mostly between 150 and 450 m in the northeastern Atlantic, and between 18 and 550 m in the northwestern Atlantic. Occurs at a temperature range of 0°-10° C (Ref. 9988). Solitary or in small groups. Feeds on crustaceans and shellfishes, benthic fishes (flatfishes and gurnard) and even on starfishes. Preyed upon by seals (Ref. 9988). Sold fresh, frozen as fillets or dried salted. Eaten steamed, fried, broiled, boiled, microwaved and baked (Ref. 9988). less ↑

Adults of this anadromous species migrate up rivers in March and April, but spawning actually takes place the following year between May and July (4). Mating occurs in pairs, unlike the other lampreys in which a female is mated by a succession of males (4). The female lays up to 300,000 eggs into a depression in the river bed created by the male. After hatching, the larvae, known as ammocoetes burrow into the sediment where they live for three to five years, feeding by filtering organic particles from the water (4). During metamorphosis, the eyes and the sucker-like mouth develop and the adults then migrate to the sea where they adopt a parasitic lifestyle, feeding by attaching to the bodies of large fish with the mouth and rasping away at the flesh. They remain in the sea for a few years and then return to freshwater in order to spawn. They do not feed during this return trip because the digestive organs degenerate, and shortly after spawning they die (4). Roman, Viking and Medieval Britons regarded river and sea lampreys as delicacies (2). less ↑